/*
* Copyright (c) GBA-NCTI-ISDC. 2022-2024.
*
* openGauss embedded is licensed under Mulan PSL v2.
* You can use this software according to the terms and conditions of the Mulan PSL v2.
* You may obtain a copy of Mulan PSL v2 at:
*
* http://license.coscl.org.cn/MulanPSL2
*
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
* MERCHANTABILITY OR FITFOR A PARTICULAR PURPOSE.
* See the Mulan PSL v2 for more details.
* -------------------------------------------------------------------------
*
* hashmap.c
*
* IDENTIFICATION
* openGauss-embedded/src/network/common/hashmap/hashmap.c
*
* -------------------------------------------------------------------------
*/

#include "hashmap.h"

#define SIZE_LOW_LIMIT 4

//hashnode
void hashnodeSetKey(HashNode node, const void *key, hash_key_type key_type)
{
    if(key != NULL)
    {
        int size = getkeySize(key_type, key);
        node->key = (unsigned char *)malloc(size);
        memcpy((unsigned char *)node->key, (unsigned char *)key, size);
    }
    else
    {
        node->key = key;
    }
}

void hashnodeSet(HashNode node, const void *key, const void *value, HashNode next, bool8 in_use, hash_key_type key_type)
{
    hashnodeSetKey(node, key, key_type);
    node->value = value;
    node->next = next;
    node->in_use = in_use;
}


//hashmap
HashMap createtHashMap(hash_key_type key_type)
{
    HashMap hash_map = newHashMap();
    hash_map->size = 0;
    hash_map->list_size = DEFAULT_LIST_SIZE;
    hash_map->key_type = key_type;
    hash_map->list = newHashNodeList(hash_map->list_size);
    HashNode p = hash_map->list;
    for (int i = 0; i < hash_map->list_size; i++)
    {
        hashnodeSet(&p[i], NULL, NULL, NULL, H_FALSE, key_type);
    }
    return hash_map;
}

void resetHashMap(HashMap hash_map, uint32 list_size) 
{

    if (list_size < DEFAULT_LIST_SIZE) 
        return;

    // 键值对临时存储空间
    HashNode tempList = newHashNodeList(hash_map->size);

    HashMapIterator iterator = createHashMapIterator(hash_map);
    int length = hash_map->size;
    for (int index = 0; nextHashMapIterator(iterator); index++)
    {
        // 迭代取出所有键值对
        hashnodeSet(&tempList[index], iterator->node->key, iterator->node->value, NULL, H_TRUE, hash_map->key_type);
        
    } 
    freeHashMapIterator(&iterator);

    // 清除原有键值对数据
    hash_map->size = 0;
    for (int i = 0; i < hash_map->list_size; i++)
    {
        HashNode node = &hash_map->list[i];
        node->key = NULL;
        node->value = NULL;
        node->in_use = H_FALSE;
        if (node->next != NULL) {
            while (node->next != NULL)
            {
                HashNode temp = node->next->next;
                free(node->next);
                node->next = temp;
            }
        }
    }

    // 更改内存大小
    hash_map->list_size = list_size;
    HashNode relist = (HashNode)realloc(hash_map->list, hash_map->list_size * sizeof(struct st_HashNode));
    if (relist != NULL) 
    {
        hash_map->list = relist;
        relist = NULL;
    }

    // 初始化数据
    for (int i = 0; i < hash_map->list_size; i++) 
    {
        hashnodeSet(&hash_map->list[i], NULL, NULL, NULL, H_FALSE, hash_map->key_type);
    }

    // 将所有键值对重新写入内存
    for (int i = 0; i < length; i++) 
    {
        HashMapPut(hash_map, tempList[i].key, tempList[i].value);
    }
    free(tempList);
}

static unsigned long crc32_tab[] =
{
      0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
      0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
      0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
      0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
      0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
      0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
      0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
      0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
      0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
      0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
      0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
      0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
      0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
      0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
      0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
      0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
      0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
      0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
      0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
      0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
      0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
      0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
      0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
      0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
      0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
      0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
      0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
      0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
      0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
      0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
      0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
      0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
      0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
      0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
      0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
      0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
      0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
      0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
      0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
      0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
      0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
      0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
      0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
      0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
      0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
      0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
      0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
      0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
      0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
      0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
      0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
      0x2d02ef8dL
   };

static unsigned long crc32(const unsigned char *s, unsigned int len)
{
  unsigned int i;
  unsigned long crc32val;
  
  crc32val = 0;
  for (i = 0;  i < len;  i ++)
    {
      crc32val = crc32_tab[(crc32val ^ s[i]) & 0xff] ^ (crc32val >> 8);
    }
  return crc32val;
}

unsigned int getkeySize(hash_key_type key_type, const void * key)
{
    unsigned int size = 0;
    if (key_type == TYPE_NUM_32)
    {
        size = sizeof(int32);
    }
    else if (key_type == TYPE_NUM_64)
    {
        size = sizeof(int64);
    }
    else
    {
        size = strlen(key) + 1;
    }
    return size;
}

unsigned char * Convert2UChar(const void * key, hash_key_type key_type, int *size)
{
    if (key_type == TYPE_STR)
    {
        *size = strlen(key);
        return (unsigned char *)key;
    }
    else
    {
        *size = getkeySize(key_type, key);
        unsigned char* uckey = (unsigned char*)malloc(*size);
        int32 num = *(int32*)key;
        for (int i = 0; i < *size; i++)
        {
            if (key_type == TYPE_NUM_32)
            {
                uckey[i] = num >> (8 * (*size - i - 1)) & 0xff;
            }
            else if (key_type == TYPE_NUM_64)
            {
                uckey[i] = num >> (8 * (*size - i - 1)) & 0xff;
            }
        }
        return uckey;
    }
    return NULL; //为了编译不报wanning
}

unsigned int HashMapHashFunc(HashMap hash_map, const void* key)
{
    int size = 0;
    unsigned char* uckey = Convert2UChar(key, hash_map->key_type, &size);
    unsigned long lkey = crc32((unsigned char*)(uckey), size);

	/* Robert Jenkins' 32 bit Mix Function */
	lkey += (lkey << 12);
	lkey ^= (lkey >> 22);
	lkey += (lkey << 4);
	lkey ^= (lkey >> 9);
	lkey += (lkey << 10);
	lkey ^= (lkey >> 2);
	lkey += (lkey << 7);
	lkey ^= (lkey >> 12);

	/* Knuth's Multiplicative Method */
	lkey = (lkey >> 3) * 2654435761;

	return lkey % hash_map->list_size;
}

void HashMapPut(HashMap hash_map, const void* key, const void* value) 
{
    
    if (hash_map->size >= hash_map->list_size) 
    {
        resetHashMap(hash_map, hash_map->list_size * 2);
    }

    int index = HashMapHashFunc(hash_map, key);
    if (hash_map->list[index].in_use == H_FALSE) 
    {
        hash_map->size++;
        // 该地址为空时直接存储
        hashnodeSetKey(&hash_map->list[index], key, hash_map->key_type);
        hash_map->list[index].value = value;
        hash_map->list[index].in_use = H_TRUE;
    }
    else 
    {
        HashNode current = &hash_map->list[index];
        while (current != NULL) {
            if (HashMapEqual(key, current->key, hash_map->key_type)) 
            {
                // 对于键值已经存在的直接覆盖
                current->value = value;
                return;
            }
            current = current->next;
        };

        //no equal key
        HashNode node = newHashNode();
        hashnodeSetKey(node, key, hash_map->key_type);
        node->value = value;
        node->in_use = H_TRUE;
        node->next = hash_map->list[index].next;
        hash_map->list[index].next = node;
        hash_map->size++;
    }
}

void* HashMapGet(HashMap hash_map, const void* key) 
{
    int index = HashMapHashFunc(hash_map, key);
    HashNode node = &hash_map->list[index];
    while (node != NULL && node->in_use != H_FALSE && HashMapEqual(node->key, key, hash_map->key_type) == H_FALSE)
    {
        node = node->next;
    }
    if(node == NULL || node->in_use == H_FALSE)
        return NULL;
    else
        return node->value;
}

bool8 HashMapRemove(HashMap hash_map, const void* key) 
{
    int index = HashMapHashFunc(hash_map, key);
    HashNode node = &hash_map->list[index];
    if (node->key == NULL) 
    {
        return H_FALSE;
    }
    bool8 result = H_FALSE;
    if (HashMapEqual(node->key, key, hash_map->key_type)) 
    {
        hash_map->size--;
        if (node->next != NULL) 
        {
            HashNode temp = node->next;
            free(node->key);
            //free(node->value); //todo 先外面释放，后续改成增加一个自定义释放函数
            node->key = temp->key;
            node->value = temp->value;
            node->next = temp->next;
            node->in_use = temp->in_use;
            free(temp);
        }
        else 
        {
            free(node->key);
            //free(node->value);//todo
            node->key = node->value = NULL;
            node->in_use = H_FALSE;
        }
        result = H_TRUE;
    }
    else {
        HashNode p = node;
        node = node->next;
        while (node != NULL) {
            if (HashMapEqual(node->key, key, hash_map->key_type)) {
                hash_map->size--;
                p->next = node->next;
                free(node->key); //todo free value
                free(node);
                result = H_TRUE;
                break;
            }
            p = node;
            node = node->next;
        };
    }

    // 如果空间占用不足1/4，则释放多余内存
    if (result &&  hash_map->size < hash_map->list_size / SIZE_LOW_LIMIT) {
        resetHashMap(hash_map, hash_map->list_size / SIZE_LOW_LIMIT);
    }
    return result;
}

void HashMapClear(HashMap hash_map) {
    for (int i = 0; i < hash_map->list_size; i++) {
        HashNode node = hash_map->list[i].next;
        while (node != NULL) {
            HashNode next = node->next;
            free(node);
            node = next;
        }
        hash_map->list[i].next = NULL;
    }
    free(hash_map->list);
    hash_map->list = NULL;
    hash_map->size = -1;
    hash_map->list_size = 0;
}

bool8 HashMapEqual(void * key1, void * key2, hash_key_type type)
{
    bool8 isEqual = H_FALSE;
    if(type == TYPE_NUM_32)
    {
        isEqual = *(int32*)key1 == *(int32*)key2;
    }
    else if(type == TYPE_NUM_64)
    {
        isEqual = *(int64*)key1 == *(int64*)key2;
    }
    else
    {
        if(strcmp((char*)key1, (char*)key2) == 0)
            isEqual = H_TRUE;
        else
            isEqual = H_FALSE; 
    }
    return isEqual;
}

//HashMapIterator
HashMapIterator createHashMapIterator(HashMap hash_map) 
{
    HashMapIterator iterator = newHashMapIterator();
    iterator->hash_map = hash_map;
    iterator->count = 0;
    iterator->hashCode = -1;
    iterator->node = NULL;
    return iterator;
}


bool8 nextHashMapIterator(HashMapIterator iterator)
{
    bool8 has_next = iterator->count < iterator->hash_map->size ? H_TRUE : H_FALSE;
    if (has_next) 
    {
        if (iterator->node != NULL && iterator->node->next != NULL) 
        {
            iterator->count++;
            iterator->node = iterator->node->next;
            return has_next;
        }
        while (++iterator->hashCode < iterator->hash_map->list_size)
        {
            HashNode node = &iterator->hash_map->list[iterator->hashCode];
            if (node->in_use) 
            {
                iterator->count++;
                iterator->node = node;
                break;
            }
        }
    }
    return has_next;
}

void freeHashMapIterator(HashMapIterator * iterator) 
{
    free(*iterator);
    *iterator = NULL;
}